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All results from a given calculation for HNO2 (Nitrous acid)

using model chemistry: MP4/3-21G*

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes CS 1A'
Energy calculated at MP4/3-21G*
 hartrees
Energy at 0K-203.872200
Energy at 298.15K-203.867803
HF Energy-203.449362
Nuclear repulsion energy64.797992
The energy at 298.15K was derived from the energy at 0K and an integrated heat capacity that used the calculated vibrational frequencies.
Vibrational Frequencies calculated at MP4/3-21G*
Rotational Constants (cm-1) from geometry optimized at MP4/3-21G*
ABC
2.63054 0.36378 0.31959

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP4/3-21G*

Point Group is Cs

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
H1 -1.842 -0.162 0.000
O2 -0.964 -0.649 0.000
N3 0.000 0.568 0.000
O4 1.194 0.173 0.000

Atom - Atom Distances (Å)
  H1 O2 N3 O4
H11.00461.98183.0547
O21.00461.55192.3085
N31.98181.55191.2575
O43.05472.30851.2575

picture of Nitrous acid state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
H1 O2 N3 99.411 O2 N3 O4 110.073
Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability